Influence of Electrochemical and Physical Characteristics of Reinforced Concrete on the Design of Cathodic Protection


The design aspect of cathodic protection of steel reinforcement embedded inconcrete; still implies a great deal of uncertainties, assumptions and specifications.Important features, such as design criteria, current distribution, and others are, as yetbeyond standardization.The main aim of this research is to study relationship between the induced levelof polarization and the area of the embedded steel, area of anode, the distance betweenthe cathode and anode and the level of applied external voltage. The experimentalprogram included preparing 12 reinforced concrete specimens with dimensions 20 x 30 x60 cm. The specimens were partially submerged in 3.5% sodium chloride solution.Various electrochemical and electrical measurement were carried out on polarized thespecimen using different external voltages.The results indicate differential moisture content within each specimen hasproduced different potentials along the steel bars. Greater polarization has always beenassociated with the submerged portion of the specimen.The results show that to achieve efficient design, the protected area should bedivided into discrete electrochemical zones depending on the concrete resistance andsteel potential.